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Around the Corner Imaging: Developing a Graphical User Interface

Description

This Creative Project was carried out in coordination with the capstone project, Around the Corner Imaging with Terahertz Waves. This capstone project deals with a system designed to implement Around the Corner, or Non Line-of-Sight (NLoS) Imaging. This document discusses

This Creative Project was carried out in coordination with the capstone project, Around the Corner Imaging with Terahertz Waves. This capstone project deals with a system designed to implement Around the Corner, or Non Line-of-Sight (NLoS) Imaging. This document discusses the creation of a GUI using MATLAB to control the Terahertz Imaging system. The GUI was developed in response to a need for synchronization, ease of operation, easy parameter modification, and data management. Along the way, many design decisions were made ranging from choosing a software platform to determining how variables should be passed. These decisions and considerations are discussed in this document. The resulting GUI has measured up to the design criteria and will be able to be used by anyone wishing to use the Terahertz Imaging System for further research in the field of Around the Corner or NLoS Imaging.

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Date Created
2019-05

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Solar Powered Quadcopter

Description

The purpose of the solar powered quadcopter is to join together the growing technologies of photovoltaics and quadcopters, creating a single unified device where the technologies harmonize to produce a new product with abilities beyond those of a traditional battery

The purpose of the solar powered quadcopter is to join together the growing technologies of photovoltaics and quadcopters, creating a single unified device where the technologies harmonize to produce a new product with abilities beyond those of a traditional battery powered drone. Specifically, the goal is to take the battery-only flight time of a quadcopter loaded with a solar array and increase that flight time by 33% with additional power provided by solar cells. The major concepts explored throughout this project are quadcopter functionality and capability and solar cell power production. In order to combine these technologies, the solar power and quadcopter components were developed and analyzed individually before connecting the solar array to the quadcopter circuit and testing the design as a whole. Several solar copter models were initially developed, resulting in multiple unique quadcopter and solar cell array designs which underwent preliminary testing before settling on a finalized design which proved to be the most effective and underwent final timed flight tests. Results of these tests are showing that the technologies complement each other as anticipated and highlight promising results for future development in this area, in particular the development of a drone running on solar power alone. Applications for a product such as this are very promising in many fields, including the industries of power, defense, consumer goods and services, entertainment, marketing, and medical. Also, becoming a more popular device for UAV hobbyists, such developments would be very appealing for leisure flying and personal photography purposes as well.

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Date Created
2015-12

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Hybrid Solar Module: Harnessing Solar Energy for Electrical and Thermal Applications

Description

A hybrid PV/T module was built, consisting of a thermal liquid heating system and a photovoltaic module system that combine in a hybrid format. This report will discuss the work on the project from Fall 2012 to Spring 2013. Three

A hybrid PV/T module was built, consisting of a thermal liquid heating system and a photovoltaic module system that combine in a hybrid format. This report will discuss the work on the project from Fall 2012 to Spring 2013. Three stages of experiments were completed. Stage 1 showed our project was functional as we were able to verify our panel produced electricity and increased the temperature of water flowing in the system by 0.65°C. Stage 2 testing included “gluing” the flow system to the back of the panel resulting in an average increase of 4.76°C in the temperature of the water in the system. Stage 3 testing included adding insulating foam to the module which resulted in increasing the average temperature of the water in our flow system by 6.95°C.

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2013-05

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Development of Frequency Selective Surfaces for RF Interrogator Design

Description

The honors thesis presented in this document describes an extension to an electrical engineering capstone project whose scope is to develop the receiver electronics for an RF interrogator. The RF interrogator functions by detecting the change in resonant frequency

The honors thesis presented in this document describes an extension to an electrical engineering capstone project whose scope is to develop the receiver electronics for an RF interrogator. The RF interrogator functions by detecting the change in resonant frequency of (i.e, frequency of maximum backscatter from) a target resulting from an environmental input. The general idea of this honors project was to design three frequency selective surfaces that would act as surrogate backscattering or reflecting targets that each contains a distinct frequency response. Using 3-D electromagnetic simulation software, three surrogate targets exhibiting bandpass frequency responses at distinct frequencies were designed and presented in this thesis.

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Date Created
2021-05

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Using Variable Gain Amplifiers to Normalize Varying Power RF Signals

Description

This thesis details the design process of a variable gain amplifier (VGA) based circuit which maintains a consistent output power over a wide range of input power signals. This effect is achieved by using power detection circuitry to adjust the

This thesis details the design process of a variable gain amplifier (VGA) based circuit which maintains a consistent output power over a wide range of input power signals. This effect is achieved by using power detection circuitry to adjust the gain of the VGA based on the current input power so that it is amplifier to a set power level. The paper details the theory behind this solutions as well as the design process which includes both simulations and physical testing of the actual circuit. It also analyses results of these tests and gives suggestions as to what could be done to further improve the design. The VGA based constant output power solution was designed as a section of a larger circuit which was developed as part of a senior capstone project, which is also briefly described in the paper.

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2021-05

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Synchrophasor Estimation and Imaging With Electric Fields and Neural Networks

Description

This research presents advances in time-synchronized phasor (i.e.,synchrophasor) estimation and imaging with very-low-frequency electric fields.
Phasor measurement units measure and track dynamic systems, often power
systems, using synchrophasor estimation algorithms. Two improvements to
subspace-based synchrophasor estimation algorithms are shown.

This research presents advances in time-synchronized phasor (i.e.,synchrophasor) estimation and imaging with very-low-frequency electric fields.
Phasor measurement units measure and track dynamic systems, often power
systems, using synchrophasor estimation algorithms. Two improvements to
subspace-based synchrophasor estimation algorithms are shown. The first
improvement is a dynamic thresholding method for accurately determining the
signal subspace when using the estimation of signal parameters via rotational
invariance techniques (ESPRIT) algorithm. This improvement facilitates
accurate ESPRIT-based frequency estimates of both the nominal system frequency
and the frequencies of interfering signals such as harmonics or out-of-band
interference signals. Proper frequency estimation of all signals present in
measurement data allows for accurate least squares estimates of synchrophasors
for the nominal system frequency. By including the effects of clutter signals
in the synchrophasor estimate, interference from clutter signals can be
excluded. The result is near-flat estimation error during nominal system
frequency changes, the presence of harmonic distortion, and out-of-band
interference. The second improvement reduces the computational burden of the
ESPRIT frequency estimation step by showing that an optimized Eigenvalue
decomposition of the measurement data can be used instead of a singular value
decomposition. This research also explores a deep-learning-based inversion
method for imaging objects with a uniform electric field and a 2D planar D-dot
array. Using electric fields as an illumination source has seen multiple
applications ranging from medical imaging to mineral deposit detection. It is
shown that a planar D-dot array and deep neural network can reconstruct the
electrical properties of randomized objects. A 16000-sample dataset of objects
comprised of a three-by-three grid of randomized dielectric constants was
generated to train a deep neural network for predicting these dielectric
constants from measured field distortions. Increasingly complex imaging
environments are simulated, ranging from objects in free space to objects
placed in a physical cage designed to produce uniform electric fields.
Finally, this research relaxes the uniform electric field constraint, showing
that the volume of an opaque container can be imaged with a copper tube antenna
and a 1x4 array of D-dot sensors. Real world experimental results
show that it is possible to image buckets of water (targets) within a plastic
shed These experiments explore the detectability of targets as a function of
target placement within the shed.

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Date Created
2021

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Techniques on Galvanically Isolated RF Chip-to-Chip Communication Circuits and Pulse-Width Modulated Class-E Power Amplifiers

Description

This thesis presents three novel studies. The first two works focus on galvanically isolated chip-to-chip communication, and the third research studies class-E pulse-width modulated power amplifiers. First, a common-mode resilient CMOS (complementary metal-oxide-semiconductor) galvanically isolated Radio Frequency (RF) chip-to-chip communication

This thesis presents three novel studies. The first two works focus on galvanically isolated chip-to-chip communication, and the third research studies class-E pulse-width modulated power amplifiers. First, a common-mode resilient CMOS (complementary metal-oxide-semiconductor) galvanically isolated Radio Frequency (RF) chip-to-chip communication system is presented utilizing laterally resonant coupled circuits to increases maximum common-mode transient immunity and the isolation capability of galvanic isolators in a low-cost standard CMOS solution beyond the limits provided from the vertical coupling. The design provides the highest reported CMTI (common-mode transient immunity) of more than 600 kV/µs, 5 kVpk isolation, and a chip area of 0.95 mm2. In the second work, a bi-directional ultra-wideband transformer-coupled galvanic isolator is reported for the first time. The proposed design merges the functionality of two isolated channels into one magnetically coupled communication, enabling up to 50% form-factor and assembly cost reduction while achieving a simultaneously robust and state-of-art performance. This work achieves simultaneous robust, wideband, and energy-efficient performance of 300 Mb/s data rate, isolation of 7.8 kVrms, and power consumption and propagation delay of 200 pJ/b and 5 ns, respectively, in only 0.8 mm2 area. The third works studies class-E pulse-width modulated (PWM) Power amplifiers (PAs). For the first time, it presents a design technique to significantly extend the Power back-off (PBO) dynamic range of PWM PAs over the prior art. A proof-of-concept watt-level class-E PA is designed using a GaN HEMT and exhibits more than 6dB dynamic range for a 50 to 30 percent duty cycle variation. Moreover, in this work, the effects of non-idealities on performance and design of class-E power amplifiers for variable supply on and pulse-width operations are characterized and studied, including the effect of non-linear parasitic capacitances and its exploitation for enhancement of average efficiency and self-heating effects in class-E SMPAs using a new over dry-ice measurement technique was presented for this first time. The non-ideality study allows for capturing a full view of the design requirement and considerations of class-E power amplifiers and provides a window to the phenomena that lead to a mismatch between the ideal and actual performance of class-E power amplifiers and their root causes.

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2021

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Millimeter-Wave and Terahertz Reconfigurable Apertures for Imaging and Wireless Communication Applications

Description

This work focuses on the analysis and design of large-scale millimeter-wave andterahertz (mmWave/THz) beamforming apertures (e.g., reconfigurable reflective surfaces–
RRSs). As such, the small wavelengths and ample bandwidths of these frequencies enable
the development of high-spatial-resolution imaging and high-throughput wireless

This work focuses on the analysis and design of large-scale millimeter-wave andterahertz (mmWave/THz) beamforming apertures (e.g., reconfigurable reflective surfaces–
RRSs). As such, the small wavelengths and ample bandwidths of these frequencies enable
the development of high-spatial-resolution imaging and high-throughput wireless
communication systems that leverage electrically large apertures to form high-gain
steerable beams.
For the rigorous evaluation of these systems’ performance in realistic application
scenarios, full-wave simulations are needed to capture all the exhibited electromagnetic
phenomena. However, the small wavelengths of mmWave/THz bands lead to enormous
meshes in conventional full-wave simulators. Thus, a novel numerical decomposition
technique is presented, which decomposes the full-wave models in smaller domains with
less meshed elements, enabling their computationally efficient analysis. Thereafter, this
method is leveraged to study a novel radar configuration that employs a rotating linear
antenna with beam steering capabilities to form 3D images. This imaging process requires
fewer elements to carry out high-spatial-resolution imaging compared to traditional 2D
phased arrays, constituting a perfect candidate in low-profile, low-cost applications.
Afterward, a high-yield nanofabrication technique for mmWave/THz graphene
switches is presented. The measured graphene sheet impedances are incorporated into
equivalent circuit models of coplanar switches to identify the optimum mmWave/THz
switch topology that would enable the development of large-scale RRSs.ii
Thereon, the process of integrating the optimized graphene switches into largescale mmWave/THz RRSs is detailed. The resulting RRSs enable dynamic beam steering
achieving 4-bits of phase quantization –for the first time in the known literature–
eliminating the parasitic lobes and increasing the aperture efficiency. Furthermore, the
devised multi-bit configurations use a single switch-per-bit topology retaining low system
complexity and RF losses. Finally, single-bit RRSs are modified to offer single-lobe
patterns by employing a surface randomization technique. This approach allows for the use
of low-complexity single-bit configurations to suppress the undesired quantization lobes
without residing to the use of sophisticated multi-bit topologies.
The presented concepts pave the road toward the implementation and proliferation
of large-scale reconfigurable beamforming apertures that can serve both as mmWave/THz
imagers and as relays or base stations in future wireless communication applications.

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Date Created
2021

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Analytic and Numerical Approaches to Radiation and Transmission of EM Waves in Lossy Media

Description

This dissertation consists of four parts: design of antenna in lossy media, analysisof wire antennas using electric field integral equation (EFIE) and wavelets, modeling and measurement of grounded waveguide coplanar waveguide (GCPW) for automotive radar, and E-Band 3-D printed antenna

This dissertation consists of four parts: design of antenna in lossy media, analysisof wire antennas using electric field integral equation (EFIE) and wavelets, modeling and measurement of grounded waveguide coplanar waveguide (GCPW) for automotive radar, and E-Band 3-D printed antenna and measurement using VNA. In the first part, the antenna is modeled and simulated in lossy media. First, the vector wave functions is solved in the fundamental mode. Next the energy flow velocity is plotted to show near-field energy distribution for both TM and TE in air and seawater environment. Finally the power relation in seawater is derived to calculate the source dipole moment and required power.
In the second part, the current distribution on the antenna is derived by solving EFIE with moment of methods (MoM). Both triangle and Coifman wavelet (Coiflet) are used as basis and weight functions. Then Input impedance of the antenna is computed and results are compared with traditional sinusoid current distribution assumption. Finally the input impedance of designed antenna is computed and matching network is designed and show resonant at designed frequency.
In the third part, GCPW is modeled and measured in E-band. Laboratory measurements are conducted in 75 to 84 GHz. The original system is embedded with error boxes due to misalignment and needed to be de-embedded. Then the measurement data is processed and the results is compared with raw data.
In the fourth part, the horn antennas and slotted waveguide array antenna (SWA) are designed for automotive radar in 75GHz to 78GHz. The horn antennas are fabricated using 3D printing of ABS material, and electro-plating with copper. The analytic solution and HFSS simulation show good agreement with measurement.

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Date Created
2021

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Intelligent Phase Shifter for mm-wave Beam Forming.

Description

Modern communication systems call for state-of-the-art links that offer almost idealistic performance. This requirement had pushed the technological world to pursue communication in frequency bands that were almost incomprehensible back when the first series of cordless cellphones were invented. These

Modern communication systems call for state-of-the-art links that offer almost idealistic performance. This requirement had pushed the technological world to pursue communication in frequency bands that were almost incomprehensible back when the first series of cordless cellphones were invented. These requirements have impacted everything from civilian requirements, space, medical diagnostics to defense technologies and have ushered in a new era of advancements. This work presents a new and novel approach towards improving the conventional phased array systems. The Intelligent Phase Shifter (IPS) offers phase tracking and discrimination solutions that currently plague High-Frequency wireless systems. The proposed system is implemented on (CMOS) process node to better scalability and reduce the overall power dissipated. A tracking system can discern Radio Frequency (RF) Signals’ phase characteristics using a double-balanced mixer. A locally generated reference signal is then matched to the phase of the incoming receiver using a fully modular yet continuous complete 360ᵒ phase shifter that alters the phase of the local reference and matches the phase with that of an incoming RF reference. The tracking is generally two control voltages that carry In-phase and Quadrature-phase information. These control signals offer the capability of controlling similar devices when placed in an array and eliminating any ambiguity that might occur due to in-band interference.

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Date Created
2021